Britain may not see a 'double-whammy' of coronavirus and flu infections this winter because social distancing measures designed to control Covid-19 have prevented influenza from spreading, experts have said.
Flu infections during the cold long months in the southern hemisphere are a canary in a coalmine for how hard the NHS will be hit by outbreaks, and are used to design the preventative flu vaccine.
But this year Australia, which has similar flu outbreaks to Britain, has seen influenza infections plunge to historic lows. After Sydney declared a lockdown on March 23, flu cases dropped from 5,895 to 308 in April, and to a low of 121 in August.
Professor Paul Hunter, an infectious disease expert at the University of East Anglia, told MailOnline Britain 'almost certainly' will not see two consecutive waves of flu and coronavirus.
'There's been virtually no influenza around in the southern hemisphere during their flu season this year and the reason for that is obvious,' he said. 'The things we're doing to control Covid are even more effective on influenza.'
It comes as the director of the US national institute of Allergy and Infectious Diseases, Dr Anthony Fauci, said the states may not see a 'double-whammy' infection wave.
And it comes amid warnings that if both hit at the same time they could cripple more than a hundred NHS trusts, which wouldn't be able to cope with the normal winter demand and level of coronavirus infections seen in April, at the peak of the pandemic.
Australia, which faces a similar flu outbreak to the UK, saw very few flu infections this winter. This suggests the UK may dodge a 'double-whammy' of coronavirus and the flu
Influenza, or the flu, is a highly contagious respiratory illness caused by influenza viruses.
It is more common during winter.
Symptoms can include fever and chills, a cough, sore throat and a runny or stuffy nose.
Muscle aches, joint pains, headaches and fatigue are also common.
Nausea, vomiting and diarrhoea are more common in children than adults.
Some symptoms may last for more than a week. Medical help should be sought if there is a shortness of breath or rapid breathing, chest pain, sudden dizziness or persistent vomiting.
Source: New South Wales Government
Speaking to MailOnline, Professor Hunter said although it was likely that Britain will not be hit by a 'double-whammy', the situation remains hard to predict.
'There is a reluctance to go to the degree of lockdown that we had early on in the year,' he said. 'Whether that and the continuing social isolation - whether that is enough to suppress a seasonal flu - is not 100 per cent certain.'
'Schools are going back and influenza does spread quite rapidly through them. We can't rule it out but it won't be anywhere near as bad as a normal flu season.'
He warned that where flu does spread it may prove more lethal if it infects someone who has also suffered from coronavirus, adding: 'One of the impacts of ordinary flu is it kills people with damaged lungs and older people.
'Covid-19 does lead to some residual lung damage. And it's quite plausible that while you get flu and you're recovering from Covid-19 you could, but we don't know for certain (that would be the impact).'
Dr Ed Hill, a post-doctoral researcher working on modelling the spread of disease at the University of Warwick, told MailOnline measures to inhibit the spread of coronavirus will also 'disrupt' influenza transmission.
'The combined interaction of non-pharmaceutical interventions, targeted at reducing Covid-19 transmission but also impacting influenza transmission, and a wide-spread and intensive vaccination campaign may reduce the scale of seasonal influenza this winter,' he said.
This year Australia's flu infections have plummeted from a peak 7,172 in February before falling sharply